Cutting The Cord For Control

Are wireless controls taking market share from their wired brethren? A report released by Navigant Research says they are. Growth in the sector is expected to continue, with annual worldwide shipments of wireless nodes for building controls forecast to surpass 36 million by 2020. One of the drivers behind the increased use of wireless controls may be that installation is relatively painless.

“Using wireless controls means less cost and disruption in existing buildings that can’t afford downtime,” said Bob Gohn, senior research director at Navigant Research, in a recent email.

Navigant Research’s report suggests that historical buildings and other similarly delicate or sensitive environments “that cannot easily be torn apart to put in wiring” may find wireless controls to be the preferred solution. Michael Day, president of HumeraTech in Rogers, Minn., pointed to a retrofit his team did several years ago.

“It was a seminary, and they had wall structures and woodwork that prohibited the normal method of installing wires after the fact,” he said.

The seminary was able to take advantage of updated technologies with the installation of about 70 wireless sensors, all without compromising the interior of the building.

In the right application, the customer’s cost-benefit analysis for wireless controls may be a little more straightforward. Wireless may be more expensive, but customers facing a difficult sensor installation are often willing to pay if it’s the only choice, Day said.

In the seminary project, a wireless solution was the best fit. Where single locations are difficult to access with conventional wires—such as at the top of a glass architectural feature or along a concrete exterior wall—wireless may also do the trick.

Mitch Slavensky, president of ACS Controls Corp., North Highlands, Calif., said he is seeing wireless controls replacing wired. And it isn’t limited to one type of technology or any particular industry. The increased usability of wireless in today’s controls environment could be the reason.

“I can take temperature, I can get pressure, and I can take signals,” Slavensky said of the current capabilities of wireless nodes.

The majority of his firm’s projects are retrofits, and the wide-ranging applications served by wireless solutions is driving more of his customers to cut the cord.

Reliability is one of the concerns customers often voice, and ECs that have not been involved with wireless controls in recent years may only remember the technology’s teething problems.

“Whether these were due to early technology, poor training or improper installation is hard to say,” Gohn said, adding that those situations may have scared some ECs away. “It does seem that the vendors today are being very cautious regarding the specifications of their wireless solutions, setting very conservative expectations regarding distances between nodes and other parameters in order to head off any issues.”

Reach was another early concern, but Slavensky said that has been largely resolved with current technology.

“I’ve been using wireless for 14 years now, and, when we first did it, we couldn’t go more than 200 or 300 feet before we needed a repeater,” he said. “Now we’re able to go through concrete and wire mesh walls and have very little problem with [signal] integrity.”

When it comes to reliability, Slavensky’s long-term experience has been that wireless nodes no longer exhibit the problems of the past.

For controls that aren’t connected to a power source, Day said he fields questions from people concerned about issues such as battery replacement. This really comes to the forefront in larger projects, where perhaps several dozen or more wireless sensors are being installed.

“They ask how often they’ll need to replace the batteries, and the answer is generally in the three-to-five-year range,” Day said. “That usually settles the issue to a certain extent, but it still becomes a maintenance issue to maintain them. It’s not unheard of that customers will opt for a wired solution over wireless even if the costs aren’t significantly different, if only to avoid putting resources into battery replacement down the road.”

For ECs just getting into the wireless control world, Slavensky strongly recommends buying testing units for any products they plan to install. This investment just might save your bacon on even simple jobs.

“Use their testing equipment, and verify you have a signal where you want to put your base device and your remote device,” Slavensky said, adding that you’ll be happier knowing the job is a success, and your customer will be pleased with the result.

Day said to remember that wireless controls are not always quite as unencumbered as the layperson might assume, a fact that can make customer conversations an educational event.

“Whether you’re controlling a [variable air volume] box or a zone, there are a lot of wires that come into play,” he said.

Wireless controls might still require wires—sometimes for power, sometimes for connection to the equipment or systems that are being monitored—so be prepared to talk about why there are still wiring costs for your wireless project.